Table 2: Performance of model fits using lab spectra of dried samples, evaluated with leave-one-out cross-validation.

pHTotal P (mg/100 g)Total K (mg/100 g)Total N (%)Total N (%)Total C (%)Total C (%)Moisture (%)

MethodPLSRPLSRPLSRPLSRSMLRPLSRSMLRPLSR

No. of factors52282292
0.500.380.790.730.800.790.950.42
RMSE CV0.4729.77193.920.260.235.172.5910.09
RPD CV1.421.282.201.932.182.224.431.33

RMSE CV: root mean square error of cross-validation, RPD CV: ratio of performance to deviation of cross-validation, PLSR: partial least squares regression, SMLR: stepwise multiple linear regression.